Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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OCN: 007J MEGAPHONE, INC.

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
857-357 A Cambridge MA CMBRMABEUMD  128      
857-357 1 Cambridge MA CMBRMABEUMD  128   2020-02-21   

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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